Dislocation-Strained IrNi Alloy Nanoparticles Driven by Thermal Shock for the Hydrogen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalyst design is critical for efficient electrochemical hydrogen production.
• Developing low-cost, high-performance catalysts remains a key challenge.

Purpose of the Study:

• To develop a novel electrocatalyst for the hydrogen evolution reaction (HER).
• To investigate the impact of dislocation-induced strain on catalyst performance.

Main Methods:

• Synthesis of dislocation-strained IrNi nanoparticles on a carbon nanotube sponge (DSIrNi@CNTS) using unsteady thermal shock.
• Electrochemical characterization of HER activity and stability.
• Density functional theory (DFT) calculations to understand strain effects.

Main Results:

• DSIrNi@CNTS exhibits outstanding HER activity with a low overpotential of 17 mV to achieve 10 mA cm⁻².
• The catalyst demonstrates excellent stability in alkaline electrolyte, outperforming commercial Pt/C.
• DFT results confirm that strain effects optimize the electronic structure and tune the HER free energy.

Conclusions:

• Dislocation-strained IrNi nanoparticles are highly effective HER catalysts.
• Strain engineering via dislocations enhances catalyst stability and activity.
• This approach offers a promising pathway for developing advanced electrocatalysts for hydrogen production.